Methods of forming semiconductor device structures, and related semiconductor device structures, semiconductor devices, and electronic systems

ABSTRACT

A method of forming a semiconductor device structure comprises forming a stack structure comprising stacked tiers. Each of the stacked tiers comprises a first structure comprising a first material and a second structure comprising a second, different material longitudinally adjacent the first structure. A patterned hard mask structure is formed over the stack structure. Dielectric structures are formed within openings in the patterned hard mask structure. A photoresist structure is formed over the dielectric structures and the patterned hard mask structure. The photoresist structure, the dielectric structures, and the stack structure are subjected to a series of material removal processes to form apertures extending to different depths within the stack structure. Dielectric structures are formed over side surfaces of the stack structure within the apertures. Conductive contact structures are formed to longitudinally extend to bottoms of the apertures. Semiconductor device structures, semiconductor devices, and electronic systems are also described.

TECHNICAL FIELD

The disclosure, in various embodiments, relates generally to the fieldof semiconductor device design and fabrication. More specifically, thedisclosure relates to methods of forming semiconductor devicestructures, and to related semiconductor device structures,semiconductor devices, and electronic systems.

BACKGROUND

A continuing goal of the semiconductor industry has been to increase thememory density (e.g., the number of memory cells per memory die) ofmemory devices, such as non-volatile memory devices (e.g., NAND Flashmemory devices). One way of increasing memory density in non-volatilememory devices is to utilize vertical memory array (also referred to asa “three-dimensional (3D) memory array”) architectures. A conventionalvertical memory array includes semiconductor pillars extending throughopenings in tiers of conductive structures (e.g., word line plates,control gate plates) and dielectric materials at each junction of thesemiconductor pillars and the conductive structures. Such aconfiguration permits a greater number of transistors to be located in aunit of die area by building the array upwards (e.g., longitudinally,vertically) on a die, as compared to structures with conventional planar(e.g., two-dimensional) arrangements of transistors.

Conventional vertical memory arrays include electrical connectionsbetween the conductive structures and access lines (e.g., word lines) sothat memory cells in the vertical memory array can be uniquely selectedfor writing, reading, or erasing operations. One method of forming suchan electrical connection includes forming a so-called “stair step” (or“staircase”) structure at edges of the tiers of conductive structures.The stair step structure includes individual “steps” defining contactregions of the conductive structures upon which contact structures canbe positioned to provide electrical access to the conductive structures.

As vertical memory array technology has advanced, additional memorydensity has been provided by forming vertical memory arrays to includeadditional tiers of conductive structures, and, hence, additional stepsin the stair step structures associated therewith. However, increasingthe number of steps of a stair step structure without undesirablyincreasing the overall width (e.g., lateral footprint) of the stair stepstructure can decrease the acceptable margin of error associated withdifferent acts in the process of forming the increased number of steps.A conventional process of forming a stair step structure may includerepeated acts of trimming a uniform width of a mask (e.g., photoresist)overlying alternating conductive structures and insulating structures,etching portions of the insulating structures not covered by a remainingportion of the mask, and then etching portions of the conductivestructures not covered by remaining portions of the insulatingstructures. Each of these repeated acts has an associated margin oferror permitting the steps of the stair step structure to be suitablysized and positioned to form contact structures thereon. As the numberof repeated acts increases, deviation from a desired step width and/or adesired step position may be compounded because errors in the sizeand/or position of one structure are transferred to subsequently formedstructures later in the process. For a large number of steps in thestair step structure, margins of error to achieve suitably sized andpositioned steps may be small, such as less than one percent (1%).Achieving such small margins of error can be very difficult usingconventional methods, which may result in improperly positioned contactstructures and may undesirably decrease yield (e.g., the number ofmemory cells that are validly programmable and erasable as a percentageof the total number of memory cells in a given batch).

In view of the foregoing, there remains a need for new semiconductordevice structures, such as memory array blocks for 3D non-volatilememory devices (e.g., 3D NAND Flash memory devices), as well as forassociated semiconductor devices and electronic systems including thenew semiconductor device structures, and simple, cost-efficient methodsof forming the new semiconductor device structures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A through 10C are partial cross-sectional (FIGS. 1A, 2A, 3A, 4A,5A, 6A, 7A, 8A, 9A, and 10A) and partial top-down (FIGS. 1B, 2B, 2C, 3B,4B, 5B, 6B, 7B, 8B, 9B, 10B, and 10C) views illustrating a method offorming a semiconductor device structure, in accordance with embodimentsof the disclosure.

FIG. 11 is a partial cutaway perspective view of a vertical memorydevice including a semiconductor device structure having a stair stepstructure, in accordance with an embodiment of the disclosure.

FIG. 12 is a schematic block diagram illustrating an electronic system,in accordance with embodiments of the disclosure.

DETAILED DESCRIPTION

Methods of forming semiconductor device structures are described, as arerelated semiconductor device structures, semiconductor devices (e.g.,vertical memory devices, such as 3D NAND Flash memory devices), andelectronic systems. In some embodiments, a method of forming asemiconductor device structure includes forming a stack structurecomprising longitudinally stacked tiers each individually including aconductive structure and an insulating structure longitudinally adjacentthe conductive structure. A hard mask structure is formed over the stackstructure, and portions of the hard mask structure are then selectivelyremoved (e.g., selectively etched) to form a patterned hard maskstructure having openings extending therethrough. Dielectric structuresare formed within the openings in the patterned hard mask structure. Aseries of material removal processes are performed after the formationof the dielectric structures to form apertures (e.g., openings, vias,trenches) extending to different depths within the stack structure. Thematerial removal processes each individually remove a portion of thephotoresist structure, one or more of the dielectric structures notcovered by a remaining portion of the photoresist structure, and one ormore portions of the stack structure not covered by one or more of thepatterned hard mask structure and the remaining portion of thephotoresist structure. Dielectric structures are formed over sidesurfaces of the stack structure within the apertures, and conductivecontact structures are then formed within remaining open spaces (e.g.,spaces unoccupied by the dielectric structures) of the apertures andlongitudinally extend to bottoms of the apertures. Optionally, prior toforming the dielectric structures within the apertures, a maskingmaterial may be formed within one or more of the apertures, and depthsof one or more other of the apertures may be increased. The maskingmaterial may then be removed, that the dielectric structures may beformed within the apertures. The methods of the disclosure may decreaseerror propagation as compared to conventional methods of forming ofsemiconductor device structures that rely on the formation of stair step(e.g., staircase) structures, and may be effectuated without increasingthe number of processing materials and/or the number of processing actsutilized by such conventional methods of forming of semiconductor devicestructures. The methods and structures of the disclosure may enhance themanufacturability of semiconductor device structures and electronicsystems, facilitating the efficient formation of semiconductive devicesand electronic systems exhibiting improved performance as compared toconventional semiconductive devices and conventional electronic systems.

The following description provides specific details, such as materialcompositions and processing conditions, in order to provide a thoroughdescription of embodiments of the present disclosure. However, a personof ordinary skill in the art would understand that the embodiments ofthe present disclosure may be practiced without employing these specificdetails. Indeed, the embodiments of the present disclosure may bepracticed in conjunction with conventional semiconductor fabricationtechniques employed in the industry. In addition, the descriptionprovided below does not form a complete process flow for manufacturing asemiconductor device (e.g., a memory device). The semiconductor devicestructures described below do not form a complete semiconductor device.Only those process acts and structures necessary to understand theembodiments of the present disclosure are described in detail below.Additional acts to form a complete semiconductor device from thesemiconductor device structures may be performed by conventionalfabrication techniques.

Drawings presented herein are for illustrative purposes only, and arenot meant to be actual views of any particular material, component,structure, device, or system. Variations from the shapes depicted in thedrawings as a result, for example, of manufacturing techniques and/ortolerances, are to be expected. Thus, embodiments described herein arenot to be construed as being limited to the particular shapes or regionsas illustrated, but include deviations in shapes that result, forexample, from manufacturing. For example, a region illustrated ordescribed as box-shaped may have rough and/or nonlinear features, and aregion illustrated or described as round may include some rough and/orlinear features. Moreover, sharp angles that are illustrated may berounded, and vice versa. Thus, the regions illustrated in the figuresare schematic in nature, and their shapes are not intended to illustratethe precise shape of a region and do not limit the scope of the presentclaims. The drawings are not necessarily to scale. Additionally,elements common between figures may retain the same numericaldesignation.

As used herein, the term “substrate” means and includes a base materialor construction upon which additional materials are formed. Thesubstrate may be a semiconductor substrate, a base semiconductor layeron a supporting structure, a metal electrode, or a semiconductorsubstrate having one or more layers, structures or regions formedthereon. The substrate may be a conventional silicon substrate or otherbulk substrate comprising a layer of semiconductive material. As usedherein, the term “bulk substrate” means and includes not only siliconwafers, but also silicon-on-insulator (SOI) substrates, such assilicon-on-sapphire (SOS) substrates and silicon-on-glass (SOG)substrates, epitaxial layers of silicon on a base semiconductorfoundation, and other semiconductor or optoelectronic materials, such assilicon-germanium, germanium, gallium arsenide, gallium nitride, andindium phosphide. The substrate may be doped or undoped. By way ofnon-limiting example, a substrate may comprise at least one of silicon,silicon dioxide, silicon with native oxide, silicon nitride, acarbon-containing silicon nitride, glass, semiconductor, metal oxide,metal, titanium nitride, carbon-containing titanium nitride, tantalum,tantalum nitride, carbon-containing tantalum nitride, niobium, niobiumnitride, carbon-containing niobium nitride, molybdenum, molybdenumnitride, carbon-containing molybdenum nitride, tungsten, tungstennitride, carbon-containing tungsten nitride, copper, cobalt, nickel,iron, aluminum, and a noble metal.

As used herein, the terms “vertical,” “longitudinal,” “horizontal,” and“lateral” are in reference to a major plane of a substrate in or onwhich the structures described are formed and are not necessarilydefined by earth's gravitational field. A “horizontal” or “lateral”direction is a direction that is substantially parallel to the majorplane of the substrate, while a “vertical” or “longitudinal” directionis a direction that is substantially perpendicular to the major plane ofthe substrate. The major plane of the substrate is defined by a surfaceof the substrate having a relatively large area compared to othersurfaces of the substrate, such as by a substantially planar circularsurface of a conventional semiconductor wafer substrate.

As used herein, spatially relative terms, such as “beneath,” “below,”“lower,” “bottom,” “above,” “upper,” “top,” “front,” “rear,” “left,”“right,” and the like, may be used for ease of description to describeone element's or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. Unless otherwise specified,the spatially relative terms are intended to encompass differentorientations of the materials in addition to the orientation depicted inthe figures. For example, if materials in the figures are inverted,elements described as “below” or “beneath” or “under” or “on bottom of”other elements or features would then be oriented “above” or “on top of”the other elements or features. Thus, the term “below” can encompassboth an orientation of above and below, depending on the context inwhich the term is used, which will be evident to one of ordinary skillin the art. The materials may be otherwise oriented (e.g., rotated 90degrees, inverted, flipped) and the spatially relative descriptors usedherein interpreted accordingly.

As used herein, the singular forms “a,” “an,” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

As used herein, “and/or” includes any and all combinations of one ormore of the associated listed items.

As used herein, the term “configured” refers to a size, shape, materialcomposition, material distribution, and arrangement of one or more of atleast one structure and at least one apparatus facilitating operation ofone or more of the structure and the apparatus in a pre-determined way.

As used herein, the term “substantially” in reference to a givenparameter, property, or condition means and includes to a degree thatone of ordinary skill in the art would understand that the givenparameter, property, or condition is met with a degree of variance, suchas within acceptable manufacturing tolerances. By way of example,depending on the particular parameter, property, or condition that issubstantially met, the parameter, property, or condition may be at least90.0% met, at least 95.0% met, at least 99.0% met, or even at least99.9% met.

As used herein, the term “about” in reference to a given parameter isinclusive of the stated value and has the meaning dictated by thecontext (e.g., it includes the degree of error associated withmeasurement of the given parameter).

FIGS. 1A through 10C are simplified partial cross-sectional (FIGS. 1A,2A, 3A, 4A, 5A, 6A, 7A, 8A, 9A, and 10A) and partial top-down (FIGS. 1B,2B, 2C, 3B, 4B, 5B, 6B, 7B, 8B, 9B, 10B, and 10C) views illustratingembodiments of a method of forming a semiconductor device structure,such as a semiconductor device structure for a vertical memory device(e.g., a 3D NAND Flash memory device). The semiconductor devicestructures formed through the methods of the disclosure may be free ofstair step (e.g., staircase) structures, such as the stair stepstructures employed by many conventional semiconductor device structures(e.g., vertical memory device structures) to facilitate electricalconnections between access lines (e.g., wordlines) and conductivestructures (e.g., control gate plates) of different tiers of a stackstructure. With the description provided below, it will be readilyapparent to one of ordinary skill in the art that the methods andstructures described herein may be used in various devices.

Referring to FIG. 1A, a semiconductor device structure 100 may include asubstrate 102, a stack structure 103 over the substrate 102, and a hardmask structure 108 over the stack structure 103. As shown in FIG. 1A,the stack structure 103 includes alternating conductive structures 104and insulating structures 106 arranged in tiers 110. For clarity andease of understanding of the drawings and related description, FIG. 1Ashows the stack structure 103 including five (5) tiers 110 of theconductive structures 104 and the insulating structures 106. A firsttier 110 a includes a first conductive structure 104 a and a firstinsulating structure 106 a over the first conductive structure 104 a; asecond tier 110 b overlies the first tier 110 a, and includes a secondconductive structure 104 b and a second insulating structure 106 b overthe second conductive structure 104 b; a third tier 110 c overlies thesecond tier 110 b, and includes a third conductive structure 104 c and athird insulating structure 106 c over the third conductive structure 104c; a fourth tier 110 d overlies the third tier 110 c, and includes afourth conductive structure 104 d and a fourth insulating structure 106d over the fourth conductive structure 104 d; and a fifth tier 110 eoverlies the fourth tier 110 d, and includes a fifth conductivestructure 104 e and a fifth insulating structure 106 e over the fifthconductive structure 104 e. However, the stack structure 103 may includea different number of tiers 110. For example, in additional embodiments,the stack structure 103 may include greater than five (5) tiers 110(e.g., greater than or equal to ten (10) tiers 110, greater than orequal to twenty-five (25) tiers 110, greater than or equal to fifty (50)tiers 110, greater than or equal to one hundred (100) tiers 110) of theconductive structures 104 and the insulating structures 106, or mayinclude less than five (5) tiers 110 (e.g., less than or equal to three(3) tiers 110) of the conductive structures 104 and the insulatingstructures 106. FIG. 1B is a top-down view of the semiconductor devicestructure 100 at the processing stage depicted in FIG. 1A.

The conductive structures 104 may be formed of and include at least oneconductive material, such as a conductively-doped semiconductor material(e.g., conductively-doped polysilicon, conductively-doped germanium,conductively-doped silicon germanium), a metal (e.g., tungsten,titanium, molybdenum, niobium, vanadium, hafnium, tantalum, chromium,zirconium, iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel,palladium, platinum, copper, silver, gold, aluminum), a metal alloy(e.g., a cobalt-based alloy, an iron-based alloy, a nickel-based alloy,an iron- and nickel-based alloy, a cobalt- and nickel-based alloy, aniron- and cobalt-based alloy, a cobalt- and nickel- and iron-basedalloy, an aluminum-based alloy, a copper-based alloy, a magnesium-basedalloy, a titanium-based alloy, a steel, a low-carbon steel, a stainlesssteel), a conductive metal-containing material (e.g., a conductive metalnitride, a conductive metal silicide, a conductive metal carbide, aconductive metal oxide), or combinations thereof In some embodiments,the conductive structures 104 are formed of and includeconductively-doped polysilicon. Each of the conductive structures 104may individually include a substantially homogeneous distribution or asubstantially heterogeneous distribution of the at least one conductivematerial. As used herein, the term “homogeneous distribution” meansamounts of a material do not vary throughout different portions (e.g.,different lateral and longitudinal portions) of a structure. Conversely,as used herein, the term “heterogeneous distribution” means amounts of amaterial vary throughout different portions of a structure. Amounts ofthe material may vary stepwise (e.g., change abruptly), or may varycontinuously (e.g., change progressively, such as linearly,parabolically) throughout different portions of the structure. In someembodiments, each of the conductive structures 104 exhibits asubstantially homogeneous distribution of conductive material. Inadditional embodiments, at least one of the conductive structures 104exhibits a substantially heterogeneous distribution of at least oneconductive material. The conductive structure 104 may, for example, beformed of and include a stack of at least two different conductivematerials. The conductive structures 104 may each be substantiallyplanar, and may each individually exhibit any desired thickness.

Each of the conductive structures 104 may be substantially the same(e.g., exhibit substantially the same material composition, averagegrain size, material distribution, size, and shape) as one another, orat least one of the conductive structures 104 may be different (e.g.,exhibit one or more of a different material composition, a differentaverage grain size, a different material distribution, a different size,and a different shape) than at least one other of the conductivestructures 104. As a non-limiting example, each of the first conductivestructure 104 a, the second conductive structure 104 b, the thirdconductive structure 104 c, the fourth conductive structure 104 d, andthe fifth conductive structure 104 e may exhibit substantially the samematerial composition, material distribution, and thickness. As anothernon-limiting example, at least one of the first conductive structure 104a, the second conductive structure 104 b, the third conductive structure104 c, the fourth conductive structure 104 d, and the fifth conductivestructure 104 e may exhibit one or more of a different materialcomposition, a different material distribution, and a differentthickness than at least one other of the first conductive structure 104a, the second conductive structure 104 b, the third conductive structure104 c, the fourth conductive structure 104 d, and the fifth conductivestructure 104 e. In some embodiments, each of the conductive structures104 is substantially the same as each other of the conductive structures104.

The insulating structures 106 may be formed of and include at least oneinsulating material, such as an oxide material (e.g., silicon dioxide,phosphosilicate glass, borosilicate glass, borophosphosilicate glass,fluorosilicate glass, titanium dioxide, zirconium dioxide, hafniumdioxide, tantalum oxide, magnesium oxide, aluminum oxide, or acombination thereof), a nitride material (e.g., silicon nitride), anoxynitride material (e.g., silicon oxynitride), amphorous carbon, or acombination thereof. In some embodiments, the insulating structures 106are formed of and include silicon dioxide. Each of the insulatingstructures 106 may individually include a substantially homogeneousdistribution or a substantially heterogeneous distribution of the atleast one insulating material. In some embodiments, each of theinsulating structures 106 exhibits a substantially homogeneousdistribution of insulating material. In additional embodiments, at leastone of the insulating structures 106 exhibits a substantiallyheterogeneous distribution of at least one conductive material. Theconductive structure 104 may, for example, be formed of and include astack (e.g., laminate) of at least two different insulating materials.The insulating structures 106 may each be substantially planar, and mayeach individually exhibit any desired thickness.

Each of the insulating structures 106 may be substantially the same(e.g., exhibit substantially the same material composition, materialdistribution, size, and shape) as one another, or at least one of theinsulating structures 106 may be different (e.g., exhibit one or more ofa different material composition, a different material distribution, adifferent size, and a different shape) than at least one other of theinsulating structures 106. As a non-limiting example, each of the firstinsulating structure 106 a, the second insulating structure 106 b, thethird insulating structure 106 c, the fourth insulating structure 106 d,and the fifth insulating structure 106 e may exhibit substantially thesame material composition, material distribution, and thickness. Asanother non-limiting example, at least one of the first insulatingstructure 106 a, the second insulating structure 106 b, the thirdinsulating structure 106 c, the fourth insulating structure 106 d, andthe fifth insulating structure 106 e may exhibit one or more of adifferent material composition, a different material distribution, and adifferent thickness than at least one other of the first insulatingstructure 106 a, the second insulating structure 106 b, the thirdinsulating structure 106 c, the fourth insulating structure 106 d, andthe fifth insulating structure 106 e. In some embodiments, each of theinsulating structures 106 is substantially the same as each other of theinsulating structures 106.

As shown in FIG. 1A, in some embodiments, the conductive structures 104and the insulating structures 106 are arranged in an alternatingsequence, beginning with one of the conductive structures 104. Inadditional embodiments, the conductive structures 104 and the insulatingstructures 106 exhibit a different arrangement relative to one another.By way of non-limiting example, the conductive structures 104 and theinsulating structures 106 may be arranged in an alternating sequencebeginning with one of the insulating structures 106. Accordingly, eachof the tiers 110 may include one of the conductive structures 104 on orover one of the insulating structures 106. A semiconductor device (e.g.,a vertical memory device, such as a 3D NAND Flash memory device)employing a semiconductor device structure having such a configurationmay have little or no difference in terms of functionality oroperability as compared to a semiconductor device employing thearrangement of the conductive structures 104 and the insulatingstructures 106 shown in FIG. 1A.

The hard mask structure 108 may be formed of and include at least onematerial (e.g., at least one hard mask material) suitable for use as anetch mask to pattern portions of the stack structure 103 (e.g., portionsof the tiers 110, including portions of the conductive structures 104and portions of the insulating structures 106) to form apertures (e.g.,openings, vias, trenches) longitudinally extending (e.g., in theZ-direction) to the conductive structures 104 (e.g., the conductivestructures 104 a through 104 e) of different tiers 110 (e.g., differenttiers 110 a through 110 e) of the stack structure 103, as described infurther detail below. By way of non-limiting example, the hard maskstructure 108 may be formed of and include at least one metal material(e.g., at least one substantially pure metal, at least one alloy, atleast one metal oxide). In some embodiments, the hard mask structure 108is formed of and includes tungsten (W). In additional embodiments, thehard mask structure 108 is formed of and includes aluminum oxide(Al₂O₃). The hard mask structure 108 may be homogeneous (e.g., mayinclude only one material layer), or may be heterogeneous (e.g., mayinclude a stack exhibiting at least two different material layers). Inaddition, the hard mask structure 108 may exhibit any thicknesspermitting desired patterning of the stack structure 103 using hard maskstructure 108, such as a thickness within a range of from about 1nanometer (nm) to about 1000 nm.

The substrate 102, the stack structure 103 (including the conductivestructures 104 and the insulating structures 106 thereof), and the hardmask structure 108 may each individually be formed using conventionalprocesses including, but not limited to, physical vapor deposition(“PVD”), chemical vapor deposition (“CVD”), atomic layer deposition(“ALD”), and/or spin-coating. PVD includes, but is not limited to, oneor more of sputtering, evaporation, and ionized PVD. Such processes areknown in the art and, therefore, are not described in detail herein.

Referring next to FIG. 2A, portions of the hard mask structure 108 (FIG.1A) are removed (e.g., etched) to form a patterned hard mask structure112 including openings 114 (e.g., apertures, vias) longitudinallyextending therethrough. As shown in FIG. 2A, the openings 114 maylongitudinally extend (e.g., in the Z-direction) completely through thepatterned hard mask structure 112, from an upper surface of thepatterned hard mask structure 112 to an upper surface of the stackstructure 103 (e.g., an upper surface of the fifth insulating structure106 e of the fifth tier 110 e of the stack structure 103). FIG. 2B is atop-down view of the semiconductor device structure 100 at theprocessing stage depicted in FIG. 2A.

The patterned hard mask structure 112 may be formed to exhibit anydesired number of the openings 114. The number of openings 114 includedin the patterned hard mask structure 112 may be substantially the sameas (e.g., equal to) or may be different than (e.g., less than, orgreater than) the number of tiers 110 in the stack structure 103. Insome embodiments, the number of openings 114 included in the patternedhard mask structure 112 is less than the number of tiers 110 in thestack structure 103. As a non-limiting example, as shown in FIG. 2A, ifthe stack structure 103 includes five (5) tiers 110 (e.g., the firsttier 110 a, the second tier 110 b, the third tier 110 c, the fourth tier110 d, and the fifth tier 110 e), the patterned hard mask structure 112may be formed to include less than or equal to four (4) openings 114(e.g., a first opening 114 a, a second opening 114 b, a third opening114 c, a fourth opening 114 d) therein. In additional embodiments,patterned hard mask structure 112 may include a different number ofopenings 114 (e.g., greater than four (4) openings 114, less than four(4) openings 114). As a non-limiting example, if the stack structure 103includes five (5) tiers 110, the patterned hard mask structure 112 maybe formed to include greater than or equal to five (5) openings 114therein.

The geometric configuration (e.g., shape, dimensions), lateral position(e.g., in the X-direction and the Y-direction shown in FIG. 2B), andlateral spacing of each of the openings 114 in the patterned hard maskstructure 112 at least partially depend on the geometric configuration,lateral position, and lateral spacing of apertures to be formed in thestack structure 103 using the patterned hard mask structure 112, asdescribed in further detail below. In turn, the geometric configuration,lateral position, and lateral spacing of each of the apertures to beformed in in the stack structure 103 may at least partially depend ongeometric configurations, lateral positions, and lateral spacing ofstructures (e.g., dielectric structures, conductive contact structures)to be formed within each of the apertures in the stack structure 103, asalso described in further detail below.

In some embodiments, the openings 114 exhibit substantially the samegeometric configurations (e.g., substantially the same shapes andsubstantially the same dimensions) as one another, are regularly (e.g.,uniformly, non-variably) laterally spaced apart (e.g., laterallyseparated, laterally distanced) from one another, and are substantiallylaterally aligned with one another. For example, as shown in FIG. 2B,each of the openings 114 may exhibit a substantially circular lateralcross-sectional shape, may have substantially the same width W₁ (e.g.,diameter), may be laterally spaced apart in the X-direction from eachother of the openings 114 laterally adjacent thereto by substantiallythe same distance D₁, and may be substantially laterally aligned in theY-direction with each other of the openings 114. The width W₁ of each ofthe openings 114 may, for example, be less than or equal to about 500 nm(e.g., less than or equal to about 400 nm, less than or equal to about300 nm). In some embodiments, the width W₁ of each of the openings 114is about 300 nm. In addition, the distance D₁ between laterally adjacentopenings 114 may, for example, be less than or equal to about 1000 nm(e.g., less than or equal to about 800 nm, less than or equal to about600 nm, less than or equal to about 500 nm, less than or equal to about400 nm, less than or equal to about 300 nm). In some embodiments, thedistance D₁ between laterally adjacent openings 114 is about 300 nm.

In additional embodiments, the patterned hard mask structure 112 isformed to exhibit a different configuration of the openings 114 thanthat depicted in FIG. 2B. By way of non-limiting example, one or more ofthe openings 114 in the patterned hard mask structure 112 may exhibit adifferent geometric configuration (e.g., a different shape, such as anon-circular lateral cross-sectional shape; and/or different dimensions,such as a smaller width or a larger width) than one or more other of theopenings 114, the openings 114 may be non-regularly (e.g.,non-uniformly, variably) laterally spaced apart from one another, and/orone or more of the openings 114 may be substantially laterally unalignedwith (e.g., laterally offset from) other of the openings 114. Forexample, as shown in the FIG. 2C, which shows a top down view of thesemiconductive device structure 100 at the processing stage depicted inFIG. 2A in accordance with additional embodiments of the disclosure, oneor more of the openings 114 may exhibit a first width W₁, and one ormore other of the openings 114 may exhibit a second width W₂ differentthan (e.g., larger than, smaller than) the first width W₁. As anotherexample, as also shown in FIG. 2C, one or more other of the openings 114may be laterally separated in the X-direction from one or more adjacentopenings 114 by a first distance D₁, and one or more of other of theopenings 114 may be laterally separated in the X-direction from one ormore other adjacent openings 114 by a second distance D₂ different than(e.g., less than, greater than) the first distance D₁. As a furtherexample, as also shown in FIG. 2C, one or more (e.g., each) of theopenings 114 may be laterally offset in the Y-direction from one or moreother of the openings 114.

With returned reference to FIG. 2A, the patterned hard mask structure112, including the openings 114 therein, may be formed usingconventional processes, such as conventional material removal processes(e.g., conventional etching processes, such as conventional dry etchingprocesses) and conventional processing equipment, which are notdescribed in detail herein.

Referring next to FIG. 3A, dielectric structures 116 are formed in theopenings 114 (FIGS. 2A and 2B) in the patterned hard mask structure 112.The dielectric structures 116 may substantially fill each of theopenings 114. For example, a first dielectric structure 116 a may beformed in and may substantially fill the first opening 114 a, a seconddielectric structure 116 b may be formed in and may substantially fillthe second opening 114 b, a third dielectric structure 116 c may beformed in and may substantially fill the third opening 114 c, and afourth dielectric structure 116 d may be formed in and may substantiallyfill the fourth opening 114d. As shown in FIG. 3A, the dielectricstructures 116 may be substantially confined (e.g., substantiallylaterally confined, substantially longitudinally confined) withinboundaries (e.g., lateral boundaries, longitudinal boundaries) of theopenings 114 (FIGS. 2A and 2B) associated therewith. Accordingly, anupper surface of each of the dielectric structures 116 may besubstantially coplanar with an upper surface of the patterned hard maskstructure 112. In additional embodiments, the dielectric structures 116may extend (e.g., laterally extend, longitudinally extend) beyond theboundaries of the openings 114. For example, the dielectric structures116 may comprise portions of the relatively larger, substantiallycontinuous structure that that covers the upper surface of the patternedhard mask structure 112 and extends into and substantially fills each ofthe openings 114. In such embodiments, an upper surface of therelatively larger, substantially continuous structure may besubstantially planar. FIG. 3B is a top-down view of the semiconductordevice structure 100 at the processing stage depicted in FIG. 3A.

The dielectric structures 116 may be formed of and include at least onedielectric material. The dielectric material may selectively etchablerelative to at least the materials of the patterned hard mask structure112 and the conductive structures 104 of the stack structure 103. Asused herein, a material is “selectively etchable” relative to anothermaterial if the material exhibits an etch rate that is at least aboutfive times (5×) greater than the etch rate of another material, such asabout ten times (10×) greater, about twenty times (20×) greater, orabout forty times (40×) greater. The dielectric structures 116 may, forexample, be formed of and include one or more of an oxide material(e.g., silicon dioxide, phosphosilicate glass, borosilicate glass,borophosphosilicate glass, fluorosilicate glass, aluminum oxide, acombination thereof), a nitride material (e.g., silicon nitride), anoxynitride material (e.g., silicon oxynitride), and amphorous carbon. Insome embodiments, the etch selectivity of the dielectric material of thedielectric structures 116 is substantially similar to the etchselectivity of the insulating material of the insulating structures 106of the stack structure 103, such that the dielectric structures 116 andthe insulating structures 106 are removed at substantially the same rateby a given etchant. In additional embodiments, the dielectric materialof the dielectric structures 116 is selectively etchable relative to theinsulating material of the insulating structures 106 of the stackstructure 103. The dielectric material of the dielectric structures 116may be the same as or may different than the insulating material of theinsulating structures 106 of the stack structure 103. In someembodiments, each of the dielectric structures 116 is formed of andincludes a silicon oxide (e.g., silicon dioxide).

The dielectric structures 116 may be formed using conventional processes(e.g., conventional deposition processes, such as one or more of aspin-on deposition process, a blanket deposition process, a PVD process,a CVD process, and an ALD process; conventional material removalprocesses, such as conventional chemical-mechanical planarization (CMP)processes) and conventional processing equipment, which are notdescribed in detail herein. By way of non-limiting example, thepatterned hard mask structure 112 may be subjected to a conventionalspin-coating process to deposit a dielectric material thereover andwithin the openings 114 (FIGS. 2A and 2B), and then at least thedeposited dielectric material may be subjected to a conventional CMPprocess to form the dielectric structures 116.

Referring next to FIG. 4A, a photoresist structure 118 is formed on orover the patterned hard mask structure 112 and the dielectric structures116. The photoresist structure 118 may serve as a mask to facilitateselective removal of one or more of the dielectric structures 116 andportions of the tiers 110 of the conductive structures 104 and theinsulating structures 106, as described in further detail below. Thephotoresist structure 118 may be formed of and include a conventionalphotoresist material, such as a conventional positive tone photoresistmaterial, or a conventional negative tone photoresist material. If thephotoresist structure 118 comprises a positive tone photoresistmaterial, the photoresist structure 118 may be formulated such thatregions thereof exposed to at least a minimum threshold dosage ofelectromagnetic radiation and, optionally, a post-exposure bake becomeat least partially soluble in a suitable developer (e.g., a positivetone developer). Photoexposed regions (e.g., regions exposed to theminimum threshold dosage of electromagnetic radiation) of thephotoresist structure 118 may be at least partially (e.g.,substantially) removed by the developer while non-photoexposed regions(e.g., regions not exposed to the minimum threshold dosage ofelectromagnetic radiation) may remain substantially intact (e.g., notsubstantially removed), as described in further detail below.Alternatively, if the photoresist structure 118 comprises a negativetone photoresist material, the photoresist structure 118 may beformulated such that regions thereof not exposed to at least a minimumthreshold dosage of electromagnetic radiation are at least partiallysoluble in a suitable developer (e.g., a negative tone developer).Non-photoexposed regions of the photoresist structure 118 may be atleast partially (e.g., substantially) removed by the developer whilephotoexposed regions may remain substantially intact (e.g., notsubstantially removed), as also described in further detail below. Theproperties (e.g., tone) of the photoresist structure 118 may be selectedrelative to material composition of the material(s) (e.g., thedielectric structures 116, the insulating structures 106, the conductivestructures 104) underlying the photoresist structure 118 to facilitatedesired patterning of the material(s), as described in further detailbelow. Suitable photoresist materials (e.g., positive tone photoresistmaterials, negative tone photoresist materials) are known in the art,and are, therefore, not described in detail herein. The photoresiststructure 118 may, for example, be compatible with 13.7 nm, 157 nm, 193nm, 248 nm, or 365 nm wavelength systems; with 193 nm wavelengthimmersion systems; and/or with electron beam lithographic systems. Inaddition, the photoresist structure 118 may exhibit any thicknesspermitting desired patterning of the stack structure 103 usingphotoresist structure 118, such as a thickness within a range of fromabout 1 nm to about 10,000 nm (e.g., about 10,000 nm). FIG. 4B is atop-down view of the semiconductor device structure 100 at theprocessing step depicted in FIG. 4A, wherein lateral boundaries of thedielectric structures 116 underlying the photoresist structure 118 aredepicted with dashed lines.

The photoresist structure 118 may be formed using conventional processesincluding, but not limited to, PVD, CVD, ALD, and/or spin-coating. Suchprocesses are known in the art and, therefore, are not described indetail herein.

Referring next to FIG. 5A, the semiconductor device structure 100 issubjected to a first material removal process to remove (e.g., trim) awidth of the photoresist structure 118 to expose (e.g., uncover) atleast one of the dielectric structures 116 (FIGS. 4A and 4B), and thenremove the at least one of the dielectric structures 116 and portions ofat least one of the tiers 110 of the stack structure 103 thereunder toform one or more apertures 120 longitudinally extending into the stackstructure 103. By way of non-limiting example, as shown in FIG. 5A, thephotoresist structure 118 may be trimmed back to a location laterallyintermediate (e.g., laterally between) the first dielectric structure116 a (FIGS. 4A and 4B) and the second dielectric structure 116 b, andthen the first dielectric structure 116 a and a portion of the fifthinsulating structure 106 e of the fifth tier 110 e of the stackstructure 103 may be selectively removed to form a first aperture 120 alongitudinally extending into the stack structure 103. The firstaperture 120 a may terminate (e.g., end, stop) at an upper surface ofthe fifth conductive structure 104 e of the fifth tier 110 e of thestack structure 103. FIG. 5B is a top-down view of the semiconductordevice structure 100 at the processing step depicted in FIG. 5A, whereinlateral boundaries of the remaining dielectric structures 116 (e.g., thesecond dielectric structure 116 b, the third dielectric structure 116 c,the fourth dielectric structure 116d) underlying a remaining portion ofthe photoresist structure 118 are depicted with dashed lines.

The first material removal process may trim any amount of thephotoresist structure 118 sufficient to substantially expose at leastone of the dielectric structures 116 (FIGS. 4A and 4B). As shown inFIGS. 5A and 5B, in some embodiments, the photoresist structure 118 istrimmed to a location about midway (e.g., equidistant) between adjacentdielectric structures 116 (e.g., about midway between the firstdielectric structure 116 a shown in FIGS. 4A and 4B and the seconddielectric structure 116 b) to substantially expose one of the adjacentdielectric structures 116 (e.g., the first dielectric structure 116 ashown in FIGS. 4A and 4B) while keeping the other of the adjacentdielectric structures 116 (e.g., the second dielectric structure 116 b)substantially covered by a remaining portion of the photoresiststructure 118. In additional embodiments, the photoresist structure 118may be trimmed to a location more laterally proximate to one of theadjacent dielectric structures 116 than the other of the adjacentdielectric structures 116 (e.g., more laterally proximate to the firstdielectric structure 116 a shown in FIGS. 4A and 4B, or more laterallyproximate to the second dielectric structure 116 b).

The first material removal process may include photolithographicallyprocessing the photoresist structure 118 to remove the width of thephotoresist structure 118, and then removing the dielectric structures116 not covered by a remaining portion of the photoresist structure 118as well as a portion of one or more of the tiers 110 of the stackstructure 103 thereunder using at least one etching process. Forexample, the photoresist structure 118 may be exposed to an appropriatewavelength (e.g., 13.7 nm, 157 nm, 193 nm, 248 nm, 365 nm) of radiationthrough a reticle and then developed to trim the width of thephotoresist structure 118 and expose (e.g., uncover) the firstdielectric structure 116 a (FIGS. 4A and 4B), and then the firstdielectric structure 116 a and a portion of the fifth insulatingstructure 106 e of the fifth tier 110 e of the stack structure 103 maybe selectively removed using at least one etching process (e.g., atleast one anisotropic etching process, such as an anisotropic dryetching process) to expose a portion of the fifth conductive structure104 e of the fifth tier 110 e of the stack structure 103. In someembodiments, such as in embodiments wherein the etch selectivity of thedielectric material of the dielectric structures 116 (FIG. 4A) issubstantially similar to the etch selectivity of the isolation materialof the fifth insulating structure 106 e, a single (e.g., only one)etching process may be used to remove the first dielectric structure 116a and the portion of the fifth insulating structure 106e thereunder. Inadditional embodiments, such as in embodiments wherein the etchselectivity of the dielectric material of the dielectric structures 116(FIG. 4A) is different than the etch selectivity of the isolationmaterial of the fifth insulating structure 106 e, a first etchingprocess may be used to remove the first dielectric structure 116 a andthen a second etching process may be used to remove the portion of thefifth insulating structure 106 e thereunder. Process parameters (e.g.,radiation wavelengths, developers, etchants, exposure times) of thefirst material removal process may be tailored to the configurations(e.g., material compositions, material distributions, thicknesses,arrangements) of the photoresist structure 118, the patterned hard maskstructure 112, and the stack structure 103 (including the configurationsof the conductive structures 104 and the insulating structures 106thereof).

Referring next to FIG. 6A, the semiconductor device structure 100 may besubjected to a second material removal process to remove (e.g., trim)another width of the photoresist structure 118 to expose (e.g., uncover)at least one other of the dielectric structures 116 (FIGS. 4A and 4B),remove the at least one other of the dielectric structures 116, andremove portions of at least two of the tiers 110 of the stack structure103 to increase the number of apertures 120 longitudinally extendinginto the stack structure 103 and increase the depth(s) of theaperture(s) 120 previously formed in the stack structure 103 (e.g.,through the first material removal process). By way of non-limitingexample, as shown in FIG. 6A, the photoresist structure 118 may betrimmed back to a location laterally intermediate (e.g., laterallybetween) the second dielectric structure 116 b (FIGS. 5A and 5B) and thethird dielectric structure 116 c; portions of the fifth conductivestructure 104 e of the fifth tier 110 e of the stack structure 103 andof the fourth insulating structure 106 d of the fourth tier 110 d of thestack structure 103 underlying the first aperture 120 a may beselectively removed to increase the depth of the first aperture 120a;and the second dielectric structure 116 b and a portion of the fifthinsulating structure 106 e of the fifth tier 110 e underlying the seconddielectric structure 116 b may be selectively removed to form a secondaperture 120 b longitudinally extending into the stack structure 103.The first aperture 120 a, as longitudinally extended during the secondmaterial removal process, may terminate at an upper surface of thefourth conductive structure 104 d of the fourth tier 110 d of the stackstructure 103. The second aperture 120 b, as formed during the secondmaterial removal process, may terminate at an upper surface of the fifthconductive structure 104 e of the fifth tier 110 e of the stackstructure 103. FIG. 6B is a top-down view of the semiconductor devicestructure 100 at the processing step depicted in FIG. 6A, whereinlateral boundaries of the remaining dielectric structures 116 (e.g., thethird dielectric structure 116 c, the fourth dielectric structure 116 d)underlying a remaining portion of the photoresist structure 118 aredepicted with dashed lines.

The second material removal process may trim any amount of thephotoresist structure 118 remaining following the first material removalprocess sufficient to substantially expose at least one of thedielectric structures 116 (FIGS. 4A and 4B) remaining after the firstmaterial removal process. As shown in FIGS. 6A and 6B, in someembodiments, the photoresist structure 118 is trimmed to a locationabout midway (e.g., equidistant) between remaining adjacent dielectricstructures 116 (e.g., about midway between the second dielectricstructure 116 b shown in FIGS. 5A and 5B and the third dielectricstructure 116 c) to substantially expose one of the remaining adjacentdielectric structures 116 (e.g., the second dielectric structure 116 bshown in FIGS. 5A and 5B) while keeping the other of the remainingadjacent dielectric structures 116 (e.g., the third dielectric structure116c) substantially covered by a further remaining portion of thephotoresist structure 118. In additional embodiments, the photoresiststructure 118 may be trimmed to a location more laterally proximate toone of the remaining adjacent dielectric structures 116 than the otherof the adjacent dielectric structures 116 (e.g., more laterallyproximate to the second dielectric structure 116 b shown in FIGS. 5A and5B, or more laterally proximate to the third dielectric structure 116c).

The second material removal process may include photolithographicallyprocessing the photoresist structure 118 remaining following the firstmaterial removal process to remove an additional width of thephotoresist structure 118; removing exposed portions of one or more ofthe conductive structures 104 using an etching process; and removingexposed dielectric structures 116, and portions of the insulatingstructures 106 uncovered following the removal of the exposed dielectricstructures 116 and the exposed portions of the conductive structures 104using another etching process. For example, the photoresist structure118 may be exposed to an appropriate wavelength of radiation through areticle and then developed to trim the additional width from thephotoresist structure 118 and expose the second dielectric structure 116b (FIGS. 5A and 5B); a portion of the fifth conductive structure 104 eof the fifth tier 110 e of the stack structure 103 may be selectivelyremoved using at least one etching process (e.g., at least oneanisotropic etching process, such as an anisotropic dry etching process)to expose a portion of the fourth insulating structure 106 d of thefourth tier 110 d of the stack structure 103; and the second dielectricstructure 116 b, a portion of the fifth insulating structure 106 e ofthe fifth tier 110 e of the stack structure 103 underlying the seconddielectric structure 116 b, and the exposed portion of the fourthinsulating structure 106 d may be selectively removed using at least oneother etching process (e.g., at least one other anisotropic etchingprocess, such as another anisotropic dry etching process) to exposeanother portion of the fifth conductive structure 104 e and a portion ofthe fourth conductive structure 104 d. The portion of the fifthconductive structure 104 e may be removed before or after the removal ofthe additional width of the photoresist structure 118, and may beremoved prior to removing the second dielectric structure 116 b and theportions of the fifth insulating structure 106 e and the fourthinsulating structure 106 d. In addition, a single (e.g., only one)etching process may be used to remove the second dielectric structure116 b and the portions of the fifth insulating structure 106 e and thefourth insulating structure 106 d, or a first etching process may beused to remove the second dielectric structure 116 b and then a secondetching process may be used to remove the portions of the fifthinsulating structure 106 e and the fourth insulating structure 106 d.The portions of the fifth insulating structure 106 e and the fourthinsulating structure 106 d may be removed substantially simultaneously.Process parameters (e.g., radiation wavelengths, developers, etchants,exposure times) of the second material removal process may be tailoredto the configurations (e.g., material compositions, materialdistributions, thicknesses, arrangements) of the photoresist structure118, the patterned hard mask structure 112, and the stack structure 103(including the configurations of the conductive structures 104 and theinsulating structures 106 thereof).

Referring next to FIG. 7A, the semiconductor device structure 100 may besubjected to additional material removal processes to remove (e.g.,trim) additional portions of the photoresist structure 118, theinsulating structures 106, and the conductive structures 104 to furtherincrease the number of apertures 120 longitudinally extending into thestack structure 103 and to further increase the depth of apertures 120previously formed in the stack structure 103 (e.g., through the firstmaterial removal process and the second material removal process). Forexample, as shown in FIG. 7A, the additional material removal processesmay increase the depths of the first aperture 120 a and the secondaperture 120 b within the stack structure 103, and may also form a thirdaperture 120 c and a fourth aperture 120 d within the stack structure103. The apertures 120 may extend to different depths within the stackstructure 103 than one another. The apertures 120 may, for example,longitudinally extend to different conductive structures 104 of thestack structure 103 than one another. By way of non-limiting example,following the additional material removal processes, the first aperture120 a may longitudinally extend to an upper surface of the secondconductive structure 104 b of the second tier 110 b of the stackstructure 103, the second aperture 120 b may longitudinally extend to anupper surface of the third conductive structure 104 c of the third tier110 c of the stack structure 103, the third aperture 120 c maylongitudinally extend to an upper surface of the fourth conductivestructure 104 d of the fourth tier 110 d of the stack structure 103, andthe fourth aperture 120 d may longitudinally extend to an upper surfaceof the fifth conductive structure 104 e of the fifth tier 110 e of thestack structure 103. FIG. 7B is a top-down view of the semiconductordevice structure 100 at the processing step depicted in FIG. 7A

While various embodiments herein are described and illustrated forclarity in the context of the semiconductor device structure 100 asbeing formed to include four (4) apertures 120 longitudinally extendingto different depths within the stack structure 103, the semiconductordevice structure 100 may, alternatively, be formed to include adifferent number of apertures 120 and/or one or more of the apertures120 may longitudinally extend to different depths than those depicted inFIG. 7A. In some embodiments, the number of apertures 120 formeddirectly corresponds to (e.g., is the same as) the number of conductivestructures 104 included in the stack structure 103. By way ofnon-limiting example, if the stack structure 103 is formed to includefifty (50) of the conductive structures 104, fifty (50) apertures 120may be formed in the semiconductor device structure 100. In additionalembodiments, the number of apertures 120 formed may be different than(e.g., less than, or greater than) the number of conductive structures104 included in the stack structure 103. By way of non-limiting example,if the stack structure 103 is formed to include fifty (50) conductivestructures 104, less than fifty (50) apertures 120 (e.g., less than orequal to forty-nine (49) apertures 120) may be formed in thesemiconductor device structure 100, or greater than fifty (50) apertures120 (e.g., greater than or equal to fifty-one (51) apertures 120) may beformed in the semiconductor device structure 100. Each of the apertures120 may longitudinally extend to a different one of the conductivestructures 104 of the stack structure 103 than each other of theapertures 120, or at least some (e.g., two or more) of the apertures 120may longitudinally extend to one or more of the same the conductivestructures 104 of the stack structure 103.

The additional material removal processes may includephotolithographically processing the photoresist structure 118 remainingfollowing previous material removal processes (e.g., the first materialremoval process, the second material removal process) to remove anadditional width of the photoresist structure 118; removing exposedportions of the conductive structures 104 using one or more etchingprocesses (e.g., one or more anisotropic etching processes, such as oneor more anisotropic dry etching processes); and removing exposeddielectric structures 116, and portions of the insulating structures 106uncovered following the removal of the exposed dielectric structures 116and the exposed portions of the conductive structures 104 using one ormore other etching processes (e.g., one or more other anisotropicetching processes, such as one or more other anisotropic dry etchingprocesses). Process parameters (e.g., radiation wavelengths, developers,etchants, exposure times) of the additional material removal processesmay be tailored to the configurations (e.g., material compositions,material distributions, thicknesses, arrangements) of the photoresiststructure 118, the patterned hard mask structure 112, and the stackstructure 103 (including the configurations of the conductive structures104 and the insulating structures 106 thereof). Duration(s) and/orend-point scheme(s) for one or more of the additional material removalprocesses may be substantially the same as or may be different thanduration(s) and/or end-point scheme(s) for one or more of the firstmaterial removal process, the second material removal process, and oneor more other of the additional material removal processes.

Referring next to FIG. 8A, optionally, one or more of the apertures 120may be at least partially (e.g., substantially) filled with a maskingmaterial 122, and then the semiconductor device structure 100 may besubjected to one or more other material removal processes (e.g., one ormore chopping processes) to increase the depth(s) of one or more otherof the aperture(s) 120 remaining unfilled with the masking material 122.For example, the masking material 122 may be disposed within the thirdaperture 120 c (FIG. 7A) and the fourth aperture 120 d (FIG. 7A), andthen the longitudinal depth of the first aperture 120 a and the secondaperture 120 b may be increased using at least one additional materialremoval process. As shown in FIG. 8A, the first aperture 120 a may belongitudinally extended to terminate at an upper surface of the firstconductive structure 104 a of the first tier 110 a of the stackstructure 103, and the second aperture 120 b may be longitudinallyextended to terminate at an upper surface of the second conductivestructure 104 b of the second tier 110 b of the stack structure 103. Themasking material 122 may substantially protect portions of the stackstructure 103 underlying the third aperture 120 c and the fourthaperture 120 d from being removed during the one or more other materialremoval processes. FIG. 8B is a top-down view of the semiconductordevice structure 100 at the optional processing step depicted in FIG.8A.

The masking material 122, if any, may be formed of and include amaterial facilitating the selective removal of portions of the stackstructure 103 (e.g., portions of the tiers 110 of the conductivestructures 104 and the insulating structures 106) underlying apertures120 (e.g., the first aperture 120 a, the second aperture 120 b)remaining substantially free of (e.g., substantially unfilled with) themasking material 122. By way of non-limiting example, the maskingmaterial 122 may be formed of and include a conventional photoresistmaterial, such as a conventional positive tone photoresist material, ora conventional negative tone photoresist material. Suitable photoresistmaterials (e.g., positive tone photoresist materials, negative tonephotoresist materials) are known in the art, and are, therefore, notdescribed in detail herein.

The masking material 122, if any, may be formed to fill any desirednumber (e.g., quantity) of the apertures 120 less than the total numberof the apertures 120. Which apertures 120 are filled with the maskingmaterial 122 (and, hence, which apertures 120 are longitudinallyextended by the one or more other material removal processes) may beselected based on desired configurations of contact structures to besubsequently formed within the apertures 120, as described in furtherdetail below. While various embodiments herein are described andillustrated for clarity in the context of the masking material 122 asbeing formed to fill two (2) of the apertures 120, the masking material122 may, alternatively, be formed to fill a different number ofapertures 120, such as greater than two (2) of the apertures 120 or lessthan two (2) of the apertures 120. As shown in FIG. 8A, in someembodiments, the masking material 122 is formed on or over surfaces(e.g., surfaces of the stack structure 103, surfaces of the patternedhard mask structure 112) within the apertures 120, and on or oversurfaces (e.g., additional surfaces of the patterned hard mask structure112) outside of the boundaries of the apertures 120. In additionalembodiments, the masking material 122 is substantially confined with theboundaries (e.g., lateral boundaries, longitudinal boundaries) of theapertures 120. The processing step depicted in FIGS. 8A and 8B maypermit subsequently formed contact structures to be provided inelectrical connection with each of the tiers 110 of the stack structure103 with fewer of the processing (e.g., photoresist structure 118trimming and stack structure 103 etching) steps previously collectivelydescribed with respect to FIGS. 5A through 7B. In further embodiments,the processing step depicted in FIGS. 8A and 8B is omitted, and themasking material 122 is absent from each of the apertures 120.

The masking material 122, if any, may be selectively formed within oneor more of the apertures 120 using conventional processes (e.g.conventional deposition processes, conventional photoexposure processes,conventional development processes) and conventional processingequipment, which are not described in detail herein. In addition,portions of the stack structure 103 underlying the apertures 120remaining unfilled with the masking material 122 may be selectivelyremoved using one or more additional conventional processes (e.g., oneor more conventional anisotropic etching processes, such as one or moreconventional anisotropic dry etching processes) and conventionalprocessing equipment, which are also not described in detail herein.

Referring next to FIG. 9A, the patterned hard mask structure 112 (FIG.7A) and, if present, the masking material 122 (FIG. 8A) may beselectively removed, and a dielectric material 124 may be formed on orover exposed surfaces of the stack structure 103 (e.g., exposed surfacesof the conductive structures 104 and the insulating structures 106). Asshown in FIG. 9A, the dielectric material 124 may extend continuouslyacross the semiconductor device structure 100, and may partially (e.g.,less than completely) fill the apertures 120 in the stack structure 103.FIG. 9B is a top-down view of the semiconductor device structure 100 atthe processing step depicted in FIG. 9A.

The patterned hard mask structure 112 (FIG. 7A) and the masking material122 (FIG. 8A, if present) may be removed using conventional processesand conventional processing equipment, which are not described in detailherein. For example, the patterned hard mask structure 112 may beremoved using at least one conventional CMP process, and the maskingmaterial 122 (if any) may be removed using at least one conventionalphotoresist development process. In additional embodiments, thepatterned hard mask structure 112 is not removed prior to forming thedielectric material 124. For example, the patterned hard mask structure112 may be substantially maintained, such that the dielectric material124 is formed on or over exposed surfaces of the patterned hard maskstructure 112, and on or over exposed surfaces of the patterned hardmask structure 112. In such embodiments, the patterned hard maskstructure 112 may be removed (e.g., using one or more conventional CMPprocesses) following the formation of the dielectric material 124, ormay be at least partially (e.g., substantially) maintained in thesemiconductor device structure 100 even after the completion of allother desired processing acts.

The dielectric material 124 may be formed of and include an oxidematerial (e.g., silicon dioxide, phosphosilicate glass, borosilicateglass, borophosphosilicate glass, fluorosilicate glass, aluminum oxide,a combination thereof), a nitride material (e.g., silicon nitride), anoxynitride material (e.g., silicon oxynitride), amphorous carbon, or acombination thereof In some embodiments, the dielectric material 124 issilicon dioxide. The dielectric material 124 may be formed at anysuitable thickness. The thickness of the dielectric material 124 may beselected (e.g., tailored) to provide electrical isolation betweencontact structures to be subsequently formed within the remaining (e.g.,unfilled) portions of the apertures 120 and some of the conductivestructures 104 of the stack structure 103. By way of non-limitingexample, the thickness of the dielectric material 124 may be less thanor equal to about 200 nm (e.g., less than or equal to about 100 nm, lessthan or equal to about 50 nm). In some embodiments, the thickness of thedielectric material 124 is less than or equal to about 100 nm. Thethickness of the dielectric material 124 may be substantially uniform,or at least one region of the dielectric material 124 may have adifferent thickness than at least one other region of the dielectricmaterial 124. The dielectric material 124 may be formed usingconventional processes (e.g., conventional deposition processes, such asone or more of a PVD process, a CVD process, and an ALD process) andconventional processing equipment, which are not described in detailherein.

Referring next to FIG. 10A, portions of the dielectric material 124 atthe bottoms (e.g., lower ends) of the apertures 120 (FIG. 9A) may beremoved, and contact structures 126 (e.g., plugs, verticalinterconnections) may be formed within the apertures 120 to provideelectrical contact to the conductive structures 104 of the tiers 110 ofthe stack structure 103. The contact structures 126 may be coupled toportions of the conductive structures 104 defining the bottoms of theapertures 120 following the removal of the portions of the dielectricmaterial 124, and may occupy volumes of the apertures 120 unoccupied byremaining portions of the dielectric material 124. Each of the contactstructures 126 may directly contact the conductive structure 104defining the bottom of the aperture 120 associated therewith, andremaining portions of the dielectric material 124 may laterallyintervene between the contact structure 126 and the conductivestructures 104 partially defining the sides of the aperture 120associated therewith. For example, as shown in FIG. 10A, a first contactstructure 126 a may be formed on a portion of the second conductivestructure 104 b defining a bottom of the first aperture 120 a (FIG. 9A),a second contact structure 126 b may be formed on a portion of the thirdconductive structure 104 c defining a bottom of the second aperture 120b (FIG. 9A), a third contact structure 126 c may be formed on a portionof the fourth conductive structure 104 d defining a bottom of the thirdaperture 120 c (FIG. 9A), and a fourth contact structure 126 d may beformed on a portion of the fifth conductive structure 104 e defining abottom of the fourth aperture 120 d (FIG. 9A). FIG. 10B is a top-downview of the semiconductor device structure 100 at the processing stepdepicted in FIG. 10A.

While various embodiments herein are described and illustrated forclarity in the context of the semiconductor device structure 100 asbeing formed to include four (4) contact structures 126, thesemiconductor device structure 100 may, alternatively, be formed toinclude a different number of contact structures 126. The number ofcontact structures 126 formed may directly correspond to the number ofapertures 120 (FIGS. 9A and 9B) (e.g., which may be the same as thenumber of tiers 110 of the stack structure 103, or may be different thanthe number of tiers 110 of the stack structure 103). By way ofnon-limiting example, if the semiconductor device structure 100 isformed to include fifty (50) apertures 120, the semiconductor devicestructure 100 may also be formed to include fifty (50) contactstructures 126 within the fifty (50) apertures 120.

The contact structures 126 may be formed of and include at least oneconductive material, such as a metal (e.g., tungsten, titanium,molybdenum, niobium, vanadium, hafnium, tantalum, chromium, zirconium,iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel, palladium,platinum, copper, silver, gold, aluminum), a metal alloy (e.g., acobalt-based alloy, an iron-based alloy, a nickel-based alloy, an iron-and nickel-based alloy, a cobalt- and nickel-based alloy, an iron- andcobalt-based alloy, a cobalt- and nickel- and iron-based alloy, analuminum-based alloy, a copper-based alloy, a magnesium-based alloy, atitanium-based alloy, a steel, a low-carbon steel, a stainless steel), aconductive metal-containing material (e.g., a conductive metal nitride,a conductive metal silicide, a conductive metal carbide, a conductivemetal oxide), a conductively-doped semiconductor material (e.g.,conductively-doped silicon, conductively-doped germanium,conductively-doped silicon germanium), or combinations thereof. Each ofthe contact structures 126 have substantially the same materialcomposition, or at least one of the contact structures 126 may have adifferent material composition than at least one other of the contactstructures 126.

In some embodiments, the contact structures 126 exhibit substantiallythe same lateral geometric configurations (e.g., substantially the samelateral cross-sectional shape and substantially the same lateraldimensions) as one another, are regularly (e.g., uniformly,non-variably) laterally spaced apart (e.g., laterally separated,laterally distanced) from one another, and are substantially laterallyaligned with one another. For example, as shown in FIG. 10B, each of thecontact structures 126 may exhibit a substantially circular lateralcross-sectional shape, may have substantially the same width W₃ (e.g.,diameter), may be laterally spaced apart in the X-direction from eachother of the contact structures 126 laterally adjacent thereto bysubstantially the same distance D₃, and may be substantially laterallyaligned in the Y-direction with each other of the contact structures126. The width W₃ of each of the openings 114 (FIGS. 2A and 2B) may, forexample, be less than or equal to about 300 nm (e.g., less than or equalto about 200 nm, less than or equal to about 100 nm). In someembodiments, the width W₃ of each of the openings 114 is about 100 nm.In addition, the distance D₃ between laterally adjacent openings 114may, for example, be less than or equal to about 1500 nm (e.g., lessthan or equal to about 1000 nm, less than or equal to about 800 nm, lessthan or equal to about 500 nm, less than or equal to about 400 nm, lessthan or equal to about 300 nm). In some embodiments, the distance D₁between laterally adjacent openings 114 is about 500 nm. The lateralgeometric configuration (e.g., lateral cross-sectional shape, lateraldimensions), lateral position (e.g., in the X-direction and theY-direction), and lateral spacing of each of the contact structures 126at least partially depends on the lateral geometric configuration,lateral position, and lateral spacing of the previously formed openings114 (FIGS. 2A and 2B) in the patterned hard mask structure 112 (FIGS. 2Aand 2B).

In additional embodiments, the semiconductor device structure 100 may beformed to exhibit a different configuration of the contact structures126 than that depicted in FIG. 10B. By way of non-limiting example, oneor more of the contact structures 126 may exhibit a different lateralgeometric configuration (e.g., a different lateral cross-sectionalshape, such as a non-circular lateral cross-sectional shape; and/ordifferent lateral dimensions, such as a smaller width or a larger width)than one or more other of the contact structures 126, the contactstructures 126 may be non-regularly (e.g., non-uniformly, variably)laterally spaced apart from one another, and/or one or more of thecontact structures 126 may be substantially laterally unaligned with(e.g., laterally offset from) other of the contact structures 126. Forexample, as shown in the FIG. 10C, which shows a top down view of thesemiconductive device structure 100 at the processing stage depicted inFIG. 10A in accordance with additional embodiments of the disclosure,one or more of the contact structures 126 may exhibit a first width W₃,and one or more other of the contact structures 126 may exhibit a secondwidth W₄ different than (e.g., larger than, smaller than) the firstwidth W₃. As another example, as also shown in FIG. 10C, one or moreother of the contact structures 126 may be laterally separated in theX-direction from one or more adjacent contact structures 126 by a firstdistance D₃, and one or more of other of the contact structures 126 maybe laterally separated in the X-direction from one or more otheradjacent contact structures 126 by a second distance D₄ different than(e.g., less than, greater than) the first distance D₃. As a furtherexample, as also shown in FIG. 10C, one or more (e.g., each) of thecontact structures 126 may be laterally offset in the Y-direction fromone or more other of the contact structures 126.

The contact structures 126 may be formed and coupled with the conductivestructures 104 of the tiers 110 of the stack structure 103 throughconventional processes (e.g., conventional material depositionprocesses, conventional material removal processes), which are notdescribed in detail herein. By way of non-limiting example, openings(e.g., vias, apertures) may be formed (e.g., etched) through thedielectric material 124 at the bottoms (e.g., lower ends) of theapertures 120 (FIG. 9A) to expose contact regions of the underlyingconductive structures 104, and then regions (e.g., volumes, open spaces)of the apertures 120 not occupied by remaining portions of thedielectric material 124 may be filled with a conductive material to formthe contact structures 126.

Thus, in accordance with embodiments of the disclosure, a method offorming a semiconductor device structure comprises forming a stackstructure comprising stacked tiers. Each of the stacked tiers comprisesa first structure comprising a first material and an second structurecomprising a second, different material longitudinally adjacent thefirst structure. A patterned hard mask structure is formed over thestack structure. Dielectric structures are formed within openings in thepatterned hard mask structure. A photoresist structure is formed overthe dielectric structures and the patterned hard mask structure. Thephotoresist structure, the dielectric structures, and the stackstructure are subjected to a series of material removal processes toselectively remove portions of the photoresist structure, portions ofthe dielectric structures not covered by remaining portions of thephotoresist structure, and portions of the stack structure not coveredby one or more of the patterned hard mask structure and the remainingportions of the photoresist structure to form apertures extending todifferent depths within the stack structure. Dielectric structures areformed over side surfaces of the stack structure within the apertures.Conductive contact structures are formed to longitudinally extend tobottoms of the apertures.

Furthermore, in accordance with additional embodiments of thedisclosure, a semiconductor device structure comprises a stack structurecomprising alternating conductive structures and insulating structuresarranged in stacked tiers overlying a substrate, and filled apertureslongitudinally extending to different depths within the stack structure.Each of the stacked tiers individually comprises one of the conductivestructures and one of the insulating structures. The stack structure isfree of stair step structures defined by edges of the stacked tiers.Each of the filled apertures individually comprises at least onedielectric structure substantially covering side surfaces of the stackstructure, and at least one conductive contact structure laterallyinwardly adjacent the at least one dielectric structure and coupled toone of the conductive structures of the stack structure.

FIG. 11 illustrates a partial cutaway perspective view of a portion of asemiconductor device 200 (e.g., a vertical memory device, such as a 3DNAND Flash memory device) including at least one semiconductor devicestructure 202 having a stack structure 203 including tiers 210 ofconductive structures 204 and insulating structures 206, and contactstructures 226 electrically connected to the conductive structures 204of the tiers 210 of the stack structure 203. The semiconductor devicestructure 202 may be free of stair step structures formed therein. Thesemiconductor device structure 202 (e.g., including the stack structure203 having the tiers 210 of the conductive structures 204 and theinsulating structures 206, and the contact structures 226) may besubstantially similar to and may be formed in substantially the samemanner as the semiconductor device structure 100 (e.g., including thestack structure 103 having the tiers 110 of the conductive structures104 and the insulating structures 106, and the contact structures 126)previously described in with respect to FIGS. 1A through 10C. Thesemiconductor device 200 may further include vertical strings 212 ofmemory cells 214 coupled to each other in series, data lines 216 (e.g.,bit lines), a source tier 218, access lines 208, first select gates 220(e.g., upper select gates, drain select gates (SGDs)), select lines 222,a second select gate 224 (e.g., a lower select gate, a source selectgate (SGS)), and additional contact structures 228. The vertical strings212 of memory cells 214 extend vertically and orthogonal to conductivelines and tiers (e.g., the data lines 216, the source tier 218, thetiers 210 of the stack structure 203, the access lines 208, the firstselect gates 220, the select lines 222, the second select gate 224), andthe contact structures 226 and the additional contact structures 228 mayelectrically couple components to each other as shown (e.g., the selectlines 222 to the first select gates 220, the access lines 208 to thetiers 210 of the stack structure 203 of the semiconductor devicestructure 202). The semiconductor device 200 may also include at leastone control device 230, which may include one or more of string drivercircuitry, pass gates, circuitry for selecting gates, circuitry forselecting conductive lines (e.g., the data lines 216, the access lines208), circuitry for amplifying signals, and circuitry for sensingsignals. The control device 230 may, for example, be electricallycoupled to the data lines 216, source tier 218, access lines 208, firstselect gates 220, and second select gate 224, for example.

Thus, in accordance with embodiments of the disclosure, a semiconductordevice comprises a stack structure comprising longitudinally alternatingconductive structures and insulating structures, the stack structurefree of stair step structures at lateral ends thereof; and conductivecontact structures within filled apertures in the stack structure andeach individually in physical contact with the one of the conductivestructures of the stack structure.

Semiconductor devices (e.g., the semiconductor device 200) includingsemiconductor device structures (e.g., the semiconductor devicestructure 202) in accordance with embodiments of the disclosure may beused in embodiments of electronic systems of the disclosure. Forexample, FIG. 12 is a block diagram of an illustrative electronic system300 according to embodiments of disclosure. The electronic system 300may comprise, for example, a computer or computer hardware component, aserver or other networking hardware component, a cellular telephone, adigital camera, a personal digital assistant (PDA), portable media(e.g., music) player, a Wi-Fi or cellular-enabled tablet such as, forexample, an iPad® or SURFACE® tablet, an electronic book, a navigationdevice, etc. The electronic system 300 includes at least one memorydevice 302. The at least one memory device 302 may include, for example,an embodiment of the semiconductor device structure 100 previouslydescribed with respect to FIGS. 10A through 10C. The electronic system300 may further include at least one electronic signal processor device304 (often referred to as a “microprocessor”). The electronic signalprocessor device 304 may, optionally, include a semiconductor devicestructure similar to an embodiment of the semiconductor device structure100 previously described with respect to FIGS. 10A through 10C. Theelectronic system 300 may further include one or more input devices 306for inputting information into the electronic system 300 by a user, suchas, for example, a mouse or other pointing device, a keyboard, atouchpad, a button, or a control panel. The electronic system 300 mayfurther include one or more output devices 308 for outputtinginformation (e.g., visual or audio output) to a user such as, forexample, a monitor, a display, a printer, an audio output jack, aspeaker, etc. In some embodiments, the input device 306 and the outputdevice 308 may comprise a single touchscreen device that can be usedboth to input information to the electronic system 300 and to outputvisual information to a user. The one or more input devices 306 andoutput devices 308 may communicate electrically with at least one of thememory device 302 and the electronic signal processor device 304.

Thus, in accordance with embodiments of the disclosure, an electronicsystem comprises a semiconductor device comprising a semiconductordevice structure, conductive line structures, and a control device. Thesemiconductor device structure comprises a stack structure comprisinglongitudinally alternating conductive structures and insulatingstructures arranged in stacked tiers, each of the stacked tierscomprising one of the conductive structures and one of the insulatingstructures; and conductive contact structures within filled apertures inthe stack structure and each individually electrically coupled to one ofthe conductive structures of the stack structure. The stack structure isfree of stair step structures located at lateral ends of the stackedtiers. The conductive line structures are electrically coupled to theconductive contact structures of the semiconductor device structure. Thecontrol device is electrically coupled to the conductive linestructures.

The methods and structures of the disclosure may substantially alleviateproblems related to the formation and processing of conventionalsemiconductive device structures including stair step (e.g., staircase)structures. The methods and structures of the disclosure may not requireas many processing acts (e.g., photolithography acts, materialdeposition acts, etching acts, planarization acts) and/or processingmaterials (e.g., fill materials, etchants) as compared to conventionalmethods of forming a semiconductor device structure including stair stepstructures, providing increased yield without a corresponding decreasein process efficiency and/or a significant increase in processing costs.In addition, the methods and structures of the disclosure do not sufferfrom the relatively small sizing and spacing error margins associatedwith properly forming stair step structures of conventionalsemiconductive device structures to receive contact structures thereon.

While the disclosure is susceptible to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and have been described in detail herein.However, the disclosure is not limited to the particular formsdisclosed. Rather, the disclosure is to cover all modifications,equivalents, and alternatives falling within the scope of the followingappended claims and their legal equivalents.

1. A method of forming a semiconductor device structure, comprising:forming a stack structure comprising stacked tiers, each of the stackedtiers comprising a first structure comprising a first material and asecond structure comprising a second, different material longitudinallyadjacent the first structure; forming a patterned hard mask structureover the stack structure; forming dielectric structures within openingsin the patterned hard mask structure; forming a photoresist structureover the dielectric structures and the patterned hard mask structure;subjecting the photoresist structure, the dielectric structures, and thestack structure to a series of material removal processes to selectivelyremove portions of the photoresist structure, portions of the dielectricstructures not covered by remaining portions of the photoresiststructure, and portions of the stack structure not covered by one ormore of the patterned hard mask structure and the remaining portions ofthe photoresist structure to form apertures extending to differentdepths within the stack structure; forming dielectric structures overside surfaces of the stack structure within the apertures, uppersurfaces of the dielectric structures substantially coplanar with anupper surface of the patterned hard mask structure; and formingconductive contact structures longitudinally extending to bottoms of theapertures.
 2. The method of claim 1, wherein forming a patterned hardmask structure over the stack structure comprises: forming a hard maskstructure comprising a metal material over the stack structure; andforming the openings in the hard mask structure.
 3. The method of claim2, wherein forming a hard mask structure comprising a metal materialover the stack structure comprises forming one or more of tungsten andaluminum oxide over the stack structure.
 4. (canceled)
 5. The method ofclaim 1, wherein subjecting the photoresist structure, the dielectricstructures, and the stack structure to a series of material removalprocesses comprises: performing a first material removal processcomprising: removing a first width of the photoresist structure touncover a first of the dielectric structures; and selectively removingthe first of the dielectric structures and a portion of the secondstructure of a first of the stacked tiers underlying the first of thedielectric structures; and performing a second material removal processafter the first material removal process, the second material removalprocess comprising: removing a second width of the photoresist structureto uncover a second of the dielectric structures; selectively removingan exposed portion of the first structure of the first of the stackedtiers; and selectively removing the second of the dielectric structures,another portion of the second structure of the first of the stackedtiers underlying the second of the dielectric structures, and a portionof the second structure of a second of the stacked tiers underlying theexposed portion of the first structure of the first of the stackedtiers.
 6. The method of claim 5, wherein selectively removing the firstof the dielectric structures and a portion of the second structure of afirst of the stacked tiers comprises subjecting the first of thedielectric structures and the first of the stacked tiers to only one dryetching process.
 7. The method of claim 5, wherein: selectively removingan exposed portion of the first structure of the first of the stackedtiers comprises subjecting the exposed portion of the first structure toa first, single dry etching process; and selectively removing the secondof the dielectric structures, another portion of the second structure ofthe first of the stacked tiers underlying the second of the dielectricstructures, and a portion of the second structure of a second of thestacked tiers underlying the exposed portion of the first structure ofthe first of the stacked tiers comprises subjecting the second of thedielectric structures, the another portion of the second structure ofthe first of the stacked tiers, and the portion of the second structureof the second of the stacked tiers to a second, single dry etchingprocess.
 8. The method of claim 1, wherein subjecting the photoresiststructure, the dielectric structures, and the stack structure to aseries of material removal processes comprises forming each of theapertures to longitudinally extend to a different one of the stackedtiers of the stacked structure than each other of the apertures.
 9. Themethod of claim 1, further comprising: forming a masking material withinone or more of the apertures prior to forming the dielectric materialover the side surfaces of the stack structure within the apertures; andincreasing depths of one or more other of the apertures after formingthe masking material within the one or more of the apertures.
 10. Themethod of claim 9, wherein: forming a masking material within one ormore of the apertures comprises forming a photoresist material oversurfaces within the one or more apertures and over additional surfacesoutside of the boundaries of the one or more apertures; and increasingdepths of one or more other of the apertures comprises selectivelyremoving portions of the first structure and the second structure of atleast one of the stacked tiers underlying the one or more other of theapertures.
 11. The method of claim 1, wherein forming dielectricstructures over side surfaces of the stack structure within theapertures comprises: forming a dielectric material substantiallycovering all exposed surfaces of the stack structure within theapertures; and removing portions of the dielectric material at thebottoms of the apertures while substantially maintaining other portionsof the dielectric material covering the side surfaces of the stackstructure within the apertures.
 12. The method of claim 1, whereinforming conductive contact structures longitudinally extending tobottoms of the apertures comprises forming the conductive contactstructures to longitudinally extend to different first structures of thestacked tiers of the stack structure.
 13. A semiconductor devicestructure, comprising: a stack structure comprising alternatingconductive structures and insulating structures arranged in stackedtiers overlying a substrate, each of the stacked tiers individuallycomprising one of the conductive structures and one of the insulatingstructures, and the stack structure free of stair step structuresdefined by edges of the stacked tiers; and filled apertureslongitudinally extending to different depths within the stack structure,a first filled aperture laterally intervening between a second filledaperture and a third filled aperture in a first lateral direction andexhibiting substantially the same lateral dimensions as the secondfilled aperture and different lateral dimensions than the third filledaperture, each of the filled apertures individually comprising: at leastone dielectric structure substantially covering side surfaces of thestack structure; and at least one conductive contact structure laterallyinwardly adjacent the at least one dielectric structure and coupled toone of the conductive structures of the stack structure.
 14. Thesemiconductor device structure of claim 13, wherein each of the filledapertures longitudinally extends to a different stacked tier of thestack structure than each other of the filled apertures.
 15. Thesemiconductor device structure of claim 13, wherein each of the filledapertures exhibits substantially the same lateral cross-sectionaldimensions and substantially the same lateral cross-sectional shape aseach other of the filled apertures.
 16. The semiconductor devicestructure of claim 13, wherein the filled apertures are substantiallyuniformly spaced apart from one another.
 17. (canceled)
 18. Thesemiconductor device structure of claim 13, wherein at least one of thefilled apertures exhibits a different lateral cross-sectional shape thanat least one other of the filled apertures.
 19. The semiconductor devicestructure of claim 13, wherein the filled apertures are non-uniformlyspaced apart from one another.
 20. (canceled)
 21. A semiconductordevice, comprising: a stack structure comprising longitudinallyalternating conductive structures and insulating structures, the stackstructure free of stair step structures at lateral ends thereof; andconductive contact structures within filled apertures in the stackstructure and each individually in physical contact with the one of theconductive structures of the stack structure, a first conductive contactstructure laterally intervening between a second conductive contactstructure and a third conductive contact structure in a first lateraldirection and exhibiting substantially the same lateral dimensions asthe second conductive contact structure and different lateral dimensionsthan the third conductive contact structure.
 22. The semiconductordevice of claim 21, wherein conductive contact structures aresubstantially laterally surrounded by a dielectric material within thefilled apertures in the stack structure.
 23. The semiconductor device ofclaim 21, wherein each of the conductive contact structureslongitudinally extends to a different one of the conductive structuresof the stack structure than each other of the conductive contactstructures.
 24. (canceled)
 25. The semiconductor device of claim 21,wherein at least one of conductive contact structures is laterallyspaced apart from at least two other of the conductive contactstructures laterally adjacent thereto by different distances.
 26. Anelectronic system, comprising: a semiconductor device comprising: asemiconductor device structure comprising: a stack structure comprisinglongitudinally alternating conductive structures and insulatingstructures arranged in stacked tiers, each of the stacked tierscomprising one of the conductive structures and one of the insulatingstructures, and the stack structure free of stair step structureslocated at lateral ends of the stacked tiers; and conductive contactstructures within filled apertures in the stack structure and eachindividually electrically coupled to one of the conductive structures ofthe stack structure, a first conductive contact structure laterallyintervening between a second conductive contact structure and a thirdconductive contact structure in a first lateral direction and exhibitingsubstantially the same lateral dimensions as the second conductivecontact structure and different lateral dimensions than the thirdconductive contact structure; conductive line structures electricallycoupled to the conductive contact structures of the semiconductor devicestructure; and a control device electrically coupled to the conductiveline structures.
 27. The semiconductor device structure of claim 13,wherein the first filled aperture is laterally adjacent the secondfilled aperture and the third filled aperture.
 28. The semiconductordevice structure of claim 13, wherein: at least two of the filledapertures laterally adjacent one another exhibit substantially the samelateral dimensions as one another; and at least two other of the filledapertures laterally adjacent one another exhibit substantially the samelateral dimensions as one another and different lateral dimensions thanthe at least two filled apertures.
 29. The semiconductor devicestructure of claim 13, wherein each of the filled apertures is partiallyaligned with each other of the filled apertures laterally adjacentthereto in the first lateral direction, and is completely unaligned witheach other of the filled apertures laterally adjacent thereto in asecond lateral direction perpendicular to the first lateral direction.30. The semiconductor device structure of claim 13, wherein lateraldimensions of at least one of the filled apertures longitudinallyextending to a first depth within the stack structure is smaller thanlateral dimensions of at least one other of the filled apertureslongitudinally extending to a second depth within the stack structureshallower than the first depth.